Float valve



H. G. OS BURN FLOAT VALVE Aug. 27, 1957 Filed Feb. 2, 1954 INVENTIOR. H6.05BURN BY 4 Fig. I

ATTORNEY FLOAT VALVE Henry G. Osburn, Oklahoma City, Okla.

Application February 2, 1954, Serial No. 407,714

Claims. (Cl. 255-28) This invention relates to improvements in drill pipe float valves adapted for use in receiving and centering aligning instruments in well bores. This application is a continuation in part of my co-pending application entitled, Drill Pipe Float Valve, Serial Number 251,887, filed October 18, 1951, now Patent No. 2,744,727.

As it is well known in the art, a well bore formed by the rotary drilling method is frequently check for vertical straightness during the drilling operation. It is the usual practice to run a centering mechanism, usually consisting of a crows foot or the like, down through the drilling string onto the top of the float valve installed in the lower end of the drilling string. An aligning instrument is then inserted through the drilling string and comes to rest upon the centering mechanism. As the drilling string is subsequently removed from the well bore, the aligning instrument indicates the vertical straightness of the well bore.

The present invention contemplates a novel float valve adapted for installation in the lower end of the drilling string and having a portion thereof adapted for receiving and centering an aligning instrument. The use of such a float valve eliminates the insertion of a supporting and centering device. in a drilling string and substantially reduces the time required for running the aligning instrument. Furthermore, my float valve is so constructed to permit a substantially unrestricted flow of drilling fluid through the valve.

An importantobject of this invention is to facilitate and reduce the time required for running an aligning instrument into a rotary drilling string.

Another object of this invention is to eliminate the necessity of running a separate centering device in a drilling string preparatory to use of an aligning instrument.

Another object of this invention is to provide a drill pipe float valve having means for receiving and centering an aligning instrument.

A further object of this invention is to provide a novel valve seat for a drill pipe float valve arranged to receive and center an aligning instrument, and which will not interfere with the normal operation of the float valve nor materially restrict the flow of circulating fluid through the drilling string.

A still further object of this invention is to provide a simply constructed combination float valve and centering device which may be economically manufactured.

Other objects and advantages of the invention will be evident from the following detailed description, read in conjunction with the accompanying drawings, which illustrate my invention.

In the drawings: v

Figure 1 is a vertical sectional view, partially in elevation, of the lower portion of a drilling string utilizing my novel float valve.

Figure,2 is a vertical sectional view of my float valve and a portion of a drilling string.

Referring to the drawings in detail, and particularly Fig. 1, reference character 2 designates a drill, collar normally suspended from a string of drill pipe (not nited States Patent Patented Aug. 27, 1957 shown) and having a drill bit 4 secured to the lower end thereof. A longitudinal bore 6 extends through the drill collar 2 to transmit circulating fluid or drilling mud downwardly from the drill pipe to the drill bit 4. A tapered and threaded counter-bore 8 is formed in the lower end 10 of the drill collar 2 to receive the threaded shank 12 of the drill bit 4. Another and smaller counter-bore 14 is formed in the drill collar 2 above the counter-bore 8 to receive a novel float valve generally indicated at 16.

The float valve 16 comprises a tubular housing 18 having a circumferential groove 20 in the outer periphery thereof adjacent each end to receive sealing rings 22. The sealing rings 22 extend outwardly from the housing 18 into contact with the walls of the counter-bore 14 and prevent a flow of drilling fluid around the housing 18. Sealing rings 24 are also secured to each end of the housing 18. The lower sealing ring 24 is anchored in a circumferential groove 26 formed in the lower end 28 of the housing 18 and extends downwardly into contact with the upper end of the drill bit shank 12. It will be observed that the lower sealing ring 24 is of a size to surround the vertical bore or fluid passageway 30 formed in the drill bit shank 12. Other passageways (not shown) are formed in the drill bit 4 to jet the drilling fluid outwardly and downwardly into the well bore (not shown) in the usual manner. The upper sealing ring 24 is anchored in a circumferential groove 32 formed in the upper end 34 of the housing 18 and extends upwardly into contact with the upper end 36 of the counter-bore 14. It will be apparent that the combined efiect of the sealing rings 22 and 24 is to prevent the drilling fluid from flowing around the housing 18 and by-passing the float valve 16, as well as reduce the abrasive effect of the drilling fluid on the counter-bore 14.

A plurality of spaced radial arms 38 extend inwardly in substantially the medial portion of the housing 18 and terminate in an apertured hub 40 disposed in the central portion of the housing 18. The hub 40 receives a tubular guide member 42 having an outwardly extending circumferential flange 44 normally resting upon the upper surface of the hub 40. A valve system 46 extends through the tubular guide 42 into the upper portion of the housing 18 for guiding a valve member 48. The guide 42 slidingly receives the valve stem 46 to retain the valve stem 46 and the valve 48 centered with respect to the housing 18. A helical compression spring 50 extends upwardly from the flange 44 around the valve stem 46 and is anchored in a recess 52 in the. lower end of the valve 48 to retain a constant upward force on the valve 48 for purposes as will be hereinafter set forth. The valve 48 is generally conical in configuration and is provided with a downwardly and outwardly tapered seating surface 54 arranged to contact a mating tapered surface 56 of a valve seat 58. A circumferential groove 60 is formed in the seating surface 54 of the valve 48 to receive a suitable sealing ring 62' which projects outwardly to engage the valve seat 58.

The valve seat 58 is tubular in form and is of a size to tightly fit in the upper end 34 of the housing 18. A circumferential groove 64 is formed in the outer periphery of the valve seat 58 to receive a suitable locking screw 66 threadedly secured in the wall of the housing 18. It will be apparent that the locking or set screw 66 secures the valve seat 58 in the desired vertical position in the housing 18. Another circumferential groove 68 is formed in the outer periphery of the valve seat 58 at the upper end thereof to cooperate with a mating groove 70 in the upper end 34 of the housing 18 for forming the sealing ring groove 32 previously described.

The valve seat 58 is also provided with a plurality- (preferably three, but not limited thereto) of circumferentially spaced arms 72 extending radially inward and upward from the upper end thereof. The arms 72 terminate in and support a centering ring 74 in a horizontal position in alignment with the center of the drill collar 2 and the bore 6. The bore 78 of the centering ring 74-. is tapered upwardly and outwardly at its upper end- Stbto receive and center an aligning instrument 82 as illus: trated in Fig. 1 and as will be more fully hereinafter set forth. 7 p 7 It will be observed from Fig. 2 that the inner diameter of the valve seat 53 is substantially equal to the bore,6 of the drill collar 2, thereby providing a smooth or non-tore bulent flow of the drilling fluid into the upper end of the float valve 16. The arms 72, being circumferentially;

spaced with substantial openings therebetween, and the ring 74, being relatively small with respect to'the diameter of the bore 6, will not materially interfere with the flow of the circulating fluid into the float valve 16. Furthermore, the arms 72 and ring 74.will not interfere with the operation of the valve 48. It will also be observed that the lower inner periphery of the housing 18 is tapered inwardly toward the lower end 28 to provide a discharge opening 84 substantially equal in diameter to the flow passageway 34) in the drill bit shank 12.

Operation The float valve 16 is installed in the drill collar 2 by unthreading the drill bit 4 and inserting the housing 18 in the counterbore 14 in the position shown in Figs. 1 and 2. When the drill bit 4 isagain threaded into the counterbore 8, the upper end of the shank 12 will contact the lower sealing ring 24 to firmly seat the housing 18 with the sealing rings 24 in contact with the upper end 36 of the counterbore 14 and the upper end of the drill bit wardly from the seat 58 and permit a substantially un-' restricted flow of the drilling fluid through the housing 18. In the event the valve stem 46 should break, the valve 48 will be caught by the guide 42, the hub 40 and arms 38 to prevent the entrance of the valve 48 into the drill bit flow passageway 30. It will be noted that the outer diameter of the valve 48 is less than the inner 1 diameter of the housing 18, therefore, the downward flow of the drilling fluid will not be stopped in any position of the valve 48 below the seat 58.

When the. downward flow of the drilling fluid is stopped, the spring, 50 will force the valve 48 upwardly into the position shown in Fig. 2 with the sealing ring 62 seated on the tapered surface 56 of the valve seat 58. The float valve 16 will then function in the usual manner to per.- mit a floating of the drilling string and prevent a retrograde or upward flow of drilling fluid through the drill collar 2. Furthermore, the float valve 16 functions as a back pressure valve in the event an unexpected pressure is encountered in the bottom of the well bore during the drilling operation. If an excessive pressure is developed below the drill bit 4 which exceeds the pressure of the drilling fluid, the valve 48 will be moved upwardly into a seated position as. shown in Fig. 2 and prevent an excessive pressure being developed in the drilling string.-

Prior to removing the drill collar 2 and drill bit 4 from a well bore, and when desired, the aligning instrument 82 may be lowered through the drilling string, including the bore 6 of the drill collar 2. The aligning instrument 82 may be of any suitable typeand lowered through the drilling string in any desired manner. As shown in Fig. l, the instrument 82 may be lowered by use of a Wire line or cable 86. The lower tapered end 88 of the aligning instrument 82 will be received in the bore 78 of the ring 74 to efliciently support and center the instrument 82 in the bore 6. The upper tapered end 80 of the bore 78 facilitates the insertion of the lower instrument end 88 into the bore 78, as well as the centering of the instrument 82., The aligning instrument 82 may then be utilized in the usual manner to determine the vertical straightness of the well bore during'removal of the drilling string.

From the foregoing, it is apparent that the present invention will materially facilitate and reduce the time required in running an aligning instrument in a rotary drilling string by eliminating the necessity of running acentering device into the drilling string before the align ing instrument. The presentfloat valve, and particularly the valve seat thereof, will efliciently receive and support the aligning instrument and will not interfere with the normal operation of the float valve or materially restrict the downward flow of drilling fluid through the drilling string.

Changes may be made in the, combination and arrange ment of parts as heretofore set forth in the specification and shown in the drawings, it being understood that any modification inthe precise embodiment of the invention may be made'within the scope of the following claims without departing from the spirit of the invention.

What is claimed is:

1. Incombination with a centering support ring for an, aligning instrument in a rotary drilling string, a float valve, comprising a tubular valve body of a size to be inserted in the drilling string, a vertically reciprocable valve in the body arranged to open downwardly, a tubular valve seat'secured in the upper portion of the body above the valve and arranged to receive the valve in a closed position thereof, said centering support ring integral, with. the, valve seatabove the valve arranged to receive andsupport an aligning instrument run into the drilling string, guide means for maintaining the valve member ,in proper position relative to the valve seat, said ring being supported in a horizontal position by a plurality of circumferentially spaced radial armsextending upwardly and inwardly from the valve seat, and sealing means provided between the valve body and the drilling string for an efficient seal therebetween.

2. In combination. with a float valve for a drill string and an aligning instrumenttherefor, a centering support having a'central bore for receiving the aligning instrument, a valve seat integral with the ,support,,a valve body member adapted to cooperate with the seat to provide alternate open and sealed positions of the valve, sealing means between the valve body and the drill string, a guide stemrintegral with the: valve body, means to slidably support the valve guide stem, a helical spring disposed around, the stem and anschored at one ,end to the valve body and at'the, opposite end to the valve stem support means to rurgethe valve body upwardly to a normally closed position.

3. In combination With a centeringsupport, having a central bore for receiving an aligning instrument for utilization with a drilling string in a rotary drilling string, a float valve comprising a cylindrical housing within the lower-portion 'of the drilling-string, sealing means between the housing and the drilling string, a spider portion secured withinthe housing, an apertured hub member integral with the spider and, disposed in coaxial relation to the housing, a, guide stern support disposed within the aperture of the hub, said, guide. stem provided with a longitudinal bore extending therethrough; a valve guide stem slidably arranged Within .the bore of the support, a valve body integral with the. top. of the stern, a

recess within the valve body, a helical spring surroundingv cooperatewith the. valve body to provide alternate posi-' tions of. open and closed forthe valve.

4. In combination with a float valve for a drill collar and an aligning instrument therefor, an apertured support adapted to receive one end portion of the aligning instrument for facilitating the centering thereof, said support integral with the valve to facilitate dispostion thereof within the drill collar, said valve comprising a cylindrical housing disposed within the lower portion of the drill collar, a plurality of sealing members provided at both ends of the housing to assure an eflicient seal between the housing and the drill collar, a spider member permanently secured Within the housing, a centrally disposed apertured hub integral with the spider and in coaxial disposition with respect to the housing, a valve stem guide rigidly disposed within the hub, said valve stem guide provided with a longitudinal bore extending therethrough, a valve stem slidably disposed within the longitudinal bore of the guide, a substantially conical shaped valve body integral with the top portion of the valve stem and guided thereby, a circular groove provided in the valve body adjacent the valve stem, a helical spring disposed around the stem and supported at one end within the groove and at the opposite end to the stem guide to urge the valve body upwardly, a sealing ring disposed around the outer periphery of the valve body, a

6 valve seat rigidly secured within the housing and adapted to cooperate with the valve body and sealing ring disposed therein to provide alternate positions of open and sealed thereof, said valve seat integral with the aligning instrument support.

5. In combination with a float valve for a drilling string and an aligning instrument therefor, a tubular housing for the float valve, a valve seat provided in the housing for cooperating with the valve, apertured centering means provided on the valve seat for receiving one end portion of the aligning instrument and sealing means between the tubular housing and drilling string.

References Cited in the file of this patent UNITED STATES PATENTS 1,505,850 Benckenstein Aug. 19, 1924 1,890,223 Kiltzer Dec. 6, 1932 1,919,510 Harrington July 25, 1933 2,109,853 Straatrnan Mar. 1, 1938 2,154,162 Hewitt, Jr. et al Apr. 11, 1939 2,219,512 Cooper et al Oct. 29, 1940 2,651,199 Collins et al. .4 Sept. 8, 1953 2,656,151 Miller Oct. 20, 1953 

